Proactive suppression is an implicit process that cannot be summoned on demand.

We examined whether proactive suppression can be applied on demand. A prompt cue indicated the to-be-ignored distractor color for each trial. Participants needed to use this cue to know which of two target shapes to respond to. To assess proactive suppression of the cued distractor color, we presented a probe letter recall task on a minority (25%) of the trials. A letter appeared inside each of the six shapes of the search array and participants recalled as many letters as they could. When the to-be-ignored color was fixed in Experiment 1, probe recall accuracy was lower for probe letters inside to-be-ignored-color distractors than target-color distractors, known as the probe suppression effect. However, when the prompted to-be-ignored color varied from trial to trial, the probe suppression effect disappeared, regardless of whether the prompt was a colored circle (Experiment 2) or a colored word (Experiment 3). Experiment 4 tested the search and destroy hypothesis by shortening the search display duration from 200 to 50 ms. No capture effect by the to-be-ignored color was evident, suggesting that participants did not first search for the to-be-ignored color, prior to suppressing it. We conclude that when rejection of a distractor color is required on demand, one cannot accomplish such suppression proactively but instead must deal with the distractor reactively, incurring a large cost in performance. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Evidence that proactive distractor suppression does not require attentional resources.

Does the suppression of irrelevant visual features require attentional resources? McDonald et al. (2023, Psychonomic Bulletin & Review, 30, 224-234) proposed that suppression processes are unavailable while a person is busy performing another task. They reported the absence of the PD (believed to index suppression) when two tasks were presented close together in time. We looked for converging evidence using established behavior measures of suppression. Following McDonald et al., our participants performed a rapid serial visual presentation (RSVP) task followed by a search task. For the RSVP task, participants determined whether the target digit 4 or 6 appeared within a string of other digits. The search display appeared at a lag of 2 or 8 digits after the RSVP target. Participants searched for a yellow target circle amongst nine background circles, which included a uniquely colored distractor for some trials. The main question was whether distractor suppression would occur at Lag 2, while attentional resources were still processing the RSVP target. Suppression was assessed using the capture-probe paradigm. On 30% of trials, probe letters appeared inside the colored circles and participants reported those letters. Probe recall accuracy was lower at locations with distractor colors than those with neutral colors (the baseline), suggesting proactive suppression. Critically, this difference in probe recall accuracy was similar at Lag 2 and Lag 8, suggesting that the ability to proactively suppress distractors remains intact while dual-tasking. We argue that although reactive suppression likely requires attentional resources, proactive suppression-an implicit process-does not.

Shattering the Attentional Window: What Really Determines Capture by Abrupt Onsets and Color Singletons?

There is emerging evidence that suppressing distractors occur to prevent capture by those distractors. Theeuwes (2022) claimed that the absence of capture is not because of suppression but rather because a difficult, serial search causes salient distractors to fall outside of the attentional window. Here, we question this attentional window view by describing evidence that (a) for color singletons, capture fails to occur with an easy search, and (b) for abrupt onsets, capture does occur in a difficult search. We argue that the critical factor determining capture by salient distractors is not the attentional window or search difficulty but rather target search mode (singleton vs. nonsingleton).

On preventing capture: Does greater salience cause greater suppression?

It has been proposed that salient objects have high potential to disrupt target performance, and so people learn to proactively suppress them, thereby preventing these salient distractors from capturing attention in the future. Consistent with this hypothesis, Gaspar et al. (Proceedings of the National Academy of Sciences, 113(13), 3693-3698, 2016) reported that the PD (believed to index suppression) was larger for high-salient color distractors than for low-salient color distractors. The present study looked for converging evidence that salience triggers suppression using established behavior measures of suppression. Following Gaspar et al., our participants searched for a yellow target circle among nine background circles, which sometimes included one circle with a unique color. The distractor was either high or low in salience with respect to the background circles. The question was whether the high-salient color would be proactively suppressed more strongly than the low-salient color. This was assessed using the capture-probe paradigm. On 33% of trials, probe letters appeared inside colored circles and participants were to report those letters. If high-salient colors are more strongly suppressed, then probe recall accuracy should be lower at locations with the high-salient color than those with the low-salient color. Experiment 1 found no such effect. A similar finding was observed in Experiment 2 after addressing possible floor effects. These findings suggest that proactive suppression is not caused by salience. We propose that the PD reflects not only proactive suppression but also reactive suppression.

Do salient abrupt onsets trigger suppression?

Many studies have indicated that abrupt onsets can capture our attention involuntarily. The present study examined whether task-irrelevant onsets trigger strong suppression of their features, to reduce the ability of the onsets to capture attention. We used a capture-probe paradigm with salient abrupt onsets as precues. Participants performed a search task (70% of the trials) with occasional probe tasks mixed in (30% of the trials). In Experiment 1, two irrelevant-color distractors appeared simultaneously with the target, one of which was always precued by the abrupt onset. The question was whether an abrupt onset cue would promote suppression of the correlated color, thereby impeding recall of probe letters at a location with that color. This did not happen. The same result was obtained in Experiment 2, despite removing the target shape from the probe display to minimize floor effects and despite presenting only one distractor color per trial to further strengthen the onset-color association. In Experiment 3, one of the two irrelevant-color distractors abruptly onsetted 50 ms before the other search elements. Despite efforts to promote suppression of the cued distractor color, probe recall accuracy was again similar for the cued and non-cued distractor colors. We conclude that distractor features are suppressed but that making them especially salient does not noticeably enhance this suppression. The suppression mechanism is therefore geared towards helping observers discriminate between target features and distractor features, not towards beating down the most threatening object.

The role of perceptual difficulty in visual hindsight bias for emotional faces.

Visual hindsight bias, also known as the "saw-it-all-along" effect, is the tendency to overestimate one's perceptual abilities with the aid of outcome knowledge. Recently, Giroux et al. (2022, Emotion, https://doi.org/10.1037/emo0001068 ) reported robust visual hindsight bias for emotional faces except for happy. We examined whether the difficulty of emotional processing could explain their finding. As in Giroux et al., participants saw a blurred image of an emotional face (happy, angry, or neutral) that progressed to clear and were instructed to stop the clearing process when they were able to identify the emotion (foresight trials). They then were shown the clearest image of each face and determined the emotion, followed by a memory task where they were asked to adjust the blur levels to indicate the point at which they had identified the emotion earlier (hindsight trials). Experiment 1 replicated Giroux et al.'s finding, showing that participants stopped the image at a higher degree of blur during the hindsight trials than they had during the foresight trials (i.e., a visual hindsight bias) for the angry and neutral faces but not happy faces. Experiment 2 manipulated the perceptual difficulty of angry and happy faces. While the easy faces replicated the results of Experiment 1, both angry and happy faces produced strong bias when made difficult. A multinomial processing tree model suggests that visual hindsight bias for emotional faces, while robust, is sensitive to perceptual processing difficulties across emotions.

The role of visual working memory capacity in attention capture among video game players.

It is well established that attention can be captured by salient distractors. Some studies have found that action video game players were less susceptible to attention capture by irrelevant distractors than non-players. Other studies have also found that individuals with greater visual working memory capacity are less susceptible to capture by irrelevant distractors than individuals with lower visual working memory capacity. The present study examined whether action video game players were less susceptible to be captured by salient distractors and, if so, whether that relationship was due to greater visual working memory capacity. Participants completed a questionnaire reporting their video game playing experience, followed by a color change detection task assessing their visual working memory capacity. They then performed an attention capture task, where they determined the orientation of a bar within a shape singleton while attempting to ignore a color singleton distractor that appeared in 50% of the trials. Results showed that action video game players did not produce less capture effect than non-action video game players. However, high visual working memory capacity individuals produced less capture effect than low visual working memory capacity individuals regardless of their video game experience. These results suggest that the ability to resist capture by irrelevant distractors may be better explained by individual differences in visual working memory capacity than by action video game experience.

On preventing attention capture: Is singleton suppression actually singleton suppression?

It is commonly assumed that salient singletons generate an "attend-to-me signal" which causes suppression to develop over time, eventually preventing capture. Despite this assumption and the name "singleton suppression," a causal link between salience and suppression has not yet been clearly established. We point out the plausibility of a simple alternative mechanism: distractors might be suppressed because they are distractors rather than targets, even when non-salient. To look for evidence of salience-based suppression, we had participants search for a target shape among distractors, which sometimes included irrelevant-colored distractors. The critical manipulation was whether the irrelevant-colored distractor was salient (a color singleton) or non-salient (three non-target colored shapes; a triplet). On 30% of trials, probe letters were presented briefly inside each shape and participants were to report those letters. Probe recall below baseline indicates suppression. Experiment 1 showed that suppression was not triggered any more strongly by salient distractors (singletons) than by non-salient distractors (triplets). Experiment 2 showed that strong suppression effects developed rapidly even in the absence of salient singletons. These findings raise the thus far neglected question of whether salience plays any role in suppression.

Multiple routes to word recognition: evidence from event-related potentials.

We used event-related potentials to determine whether lexical access during semantic processing is achieved solely by the letter-based route, or by both a letter-based and word-based route. Participants determined whether words were related or unrelated to a prespecified category. To disrupt the word-based route (i.e., disrupt the processing of overall word shape), we manipulated case type. We measured the N170, assumed to be an index of holistic processing, and the N400, an index of semantic activation. Surprisingly, mixed-case words elicited a larger N170 effect than either consistent lowercase words (Experiment 1) or consistent uppercase words (Experiment 2). The N400, meanwhile, was unaffected by case mixing. In contrast, LEET words (e.g., T4BL3 instead of TABLE), which preserve overall word shape but distort letter shape, increased the N400 but did not reduce the N170 (Experiment 3). The results indicate that the N170 is in fact not a reliable index of holistic word processing. Implications for word recognition models are discussed.

Case mixing impedes early lexical access: converging evidence from the masked priming paradigm.

When letters are presented in mixed case (e.g., "PlAnE), word recognition is slowed. This case-mixing effect has been used to argue that early stages of word recognition operate holistically (on the entire visual word form) rather than merely letter-by-letter. Contrary to this holistic view, however, a masked priming study (Perea, Vergara-Martínez, & Gomez, Cognition 142:39-43, 2015) with Spanish words argued that case mixing has no effect on early stages of visual word recognition. Their participants made lexical decisions on an uppercase target (e.g., "PLANE") preceded by an identical prime (e.g., "plane") or an unrelated prime (e.g., "music"), presented in lowercase or mixed case. Because priming effects (unrelated-identical) were unaffected by case mixing, they concluded that case mixing does not impede early lexical access. We examined whether this finding applies to English words, while also including lowercase targets to prevent a strong bias against holistic word recognition. We found larger priming effects from lowercase primes than mixed-case primes regardless of target case (lowercase vs. uppercase) and whether target case was varied within blocks (Experiment 1) or between blocks (Experiment 2). Contrary to Perea et al.'s findings for Spanish, our results suggest an early locus for the case-mixing effect, consistent with the holistic view of word recognition.

An Electrophysiological Study of Aging and Perceptual Letter-Matching.

Background: Previous studies on perceptual letter-matching have found that younger and older adults showed "fast-same" effects for response time and "false-different" effects for errors but the effects were more pronounced for older adults. According to the Noisy Operator Theory, internal noise in visual processing distorts "same" trials into appearing different whereas distortion for "different" trials does not affect performance. Older adults have a "noisier" representation of items within perceptual processing which can impact perceptual matching. However, EEG measures may provide a more direct measure of letter-matching decisions. Methods: We measured the P300 event-related potential (ERP) amplitude, an index of familiarity in stimulus categorization, and behavioral measures (response time and accuracy) to assess letter-matching performance. Results: Individuals responded faster to "same" trials than to "different" trials but were less accurate. Older adults showed similar P300 amplitudes across trial type whereas younger adults produced a larger amplitude for "same" than "different" trials, suggesting that older adults showed less familiarity for "same" trials than did younger adults - a prediction of the Noisy Operator Theory. Conclusions: These ERP results are consistent with the Noisy Operator Theory - suggesting that an age-related increase in internal noise affected letter-matching performance.

Emotion-induced attentional bias: does it modulate the spatial Simon effect?

Schlaghecken, F., Blagrove, E., Mantantzis, K., Maylor, E. A., & Watson, D. G. [(2017). Look on the bright side: Positivity bias modulates interference effects in the Simon task. Journal of Experimental Psychology: General, 146(6), 763-770] found larger spatial Simon effects for happy than sad faces. Unexpectedly, this enhancement was also observed for nonvalenced objects requiring the same response as happy faces. We examined whether the increase of the spatial Simon effect is location- or object-based. In Experiments 1 and 2, participants pressed a left/right key in response to a happy/sad face or a left-/right-pointing arrow. These stimuli appeared on the left/right side of fixation, with location being task-irrelevant. Consistent with Schlaghecken et al., the spatial Simon effect was numerically larger for happy than sad faces regardless of whether faces and arrows were presented in different blocks (Experiment 1) or intermixed within blocks (Experiment 2). However, the spatial Simon effect for arrows was not modulated by the faces' emotional valence. Similar findings were observed with pointing hands in Experiment 3. Our results imply that attentional bias is associated with specific objects (e.g. faces) not locations.

Evidence of Neural Microstructure Abnormalities in Type I Chiari Malformation: Associations Among Fiber Tract Integrity, Pain, and Cognitive Dysfunction.

BACKGROUND: Previous case-control investigations of type I Chiari malformation (CMI) have reported cognitive deficits and microstructural white matter abnormalities, as measured by diffusion tensor imaging (DTI). CMI is also typically associated with pain, including occipital headache, but the relationship between pain symptoms and microstructure is not known. METHODS: Eighteen CMI patients and 18 adult age- and education-matched control participants underwent DTI, were tested using digit symbol coding and digit span tasks, and completed a self-report measure of chronic pain. Tissue microstructure indices were used to examine microstructural abnormalities in CMI as compared with healthy controls. Group differences in DTI parameters were then reassessed after controlling for self-reported pain. Finally, DTI parameters were correlated with performance on the digit symbol coding and digit span tasks within each group. RESULTS: CMI patients exhibited greater fractional anisotropy (FA), lower radial diffusivity, and lower mean diffusivity in multiple brain regions compared with controls in diffuse white matter regions. Group differences no longer existed after controlling for self-reported pain. A significant correlation between FA and the Repeatable Battery for the Assessment of Neuropsychological Status coding performance was observed for controls but not for the CMI group. CONCLUSIONS: Diffuse microstructural abnormalities appear to be a feature of CMI, manifesting predominantly as greater FA and less diffusivity on DTI sequences. These white matter changes are associated with the subjective pain experience of CMI patients and may reflect reactivity to neuroinflammatory responses. However, this hypothesis will require further deliberate testing in future studies.

Type I Chiari malformation, RBANS performance, and brain morphology: Connecting the dots on cognition and macrolevel brain structure.

BACKGROUND: Idiopathic descent of cerebellar tonsils into the cervical spine in Chiari malformation Type I (CMI) is typically associated with occipital headache. Accumulating evidence from experimental studies suggests cognitive effects of CMI. The aim of the current study was to examine the relationship between cognition and CMI using a battery of standardized neuropsychological and symptom inventory instruments. METHOD: Eighteen untreated adults with CMI, and 18 gender, age, and education matched healthy controls completed the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), and standardized measures of pain, mood, and disability. Morphometric measurements of key neural and osseous elements were also obtained from structural brain magnetic resonance images, for correlation with symptom outcomes. RESULTS: CMI patients exhibited deficits in RBANS attention, immediate memory, delayed memory, and total score. After controlling for pain and associated affective disturbance, the significant group effect for RBANS attention remained. CMI patients also presented seven morphometric differences comprising the cerebellum and posterior cranial fossa compartment that differed from healthy controls, some of which were associated with self-reported pain and disability. Notably, group differences in tonsillar position were associated with self-reported pain, disability, and delayed memory. CONCLUSION: Adult CMI is associated with domain-specific cognitive change, detectable using a standard clinical instrument. The extent of cognitive impairment is independent of pain or affective symptomatology and may be related to the key pathognomonic feature of the condition. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Emotional arousal deficit or emotional regulation bias? An electrophysiological study of age-related differences in emotion perception.

Background/Study context: Adult age differences in emotion processing have been attributed to age-related decline in earlier emotional perception and age-related bias in later emotional regulation. Yet, the relationship between the processes of early emotion perception and bias in emotional regulation and their influence on behavioral outcomes remains unclear. Event-related potentials (ERPs) have the temporal precision to allow for the online measure of neurophysiological activity and provide potential insight into the complex dynamics of emotion processing and aging. METHODS: ERPs were used as the primary measure to examine the hypotheses that younger adults will differ in emotional arousal and emotional bias as represented by the early P1 waveform and later P3 waveform, respectively. Thirty-two younger and older adults (16 each) performed a facial emotion discrimination task in which they identified standardized angry, happy, or neutral expressions of faces from the NimStim database. RESULTS: Younger adults showed a greater P1 ERP for angry faces relative to happy faces at parietal channels, while older adults did not exhibit any emotional modulation of the P1. In contrast, both younger and older adults showed a greater late P3 ERP for angry faces compared to happy faces. CONCLUSION: The authors' results provide evidence for an age-related deficit in early emotion perception and autonomic arousal. Younger adults, but not older adults, exhibited a pattern of neurophysiological activity believed to reflect preconscious and reflexive identification of threat. Despite these age group differences in early emotion processing, younger and older adults did not exhibit differences in neurophysiological processes believed to reflect emotion regulation.

An Electrophysiological Study of Cognitive and Emotion Processing in Type I Chiari Malformation.

Type I Chiari malformation (CMI) is a neurological condition in which the cerebellar tonsils descend into the cervical spinal subarachnoid space resulting in cervico-medullary compression. Early case-control investigations have indicated cognitive deficits in the areas of attention, memory, processing speed, and visuospatial function. The present study further examined cognitive and emotional processing deficits associated with CMI using a dual-task paradigm. Nineteen CMI patients were recruited during pre-surgical consultation and 19 matched control participants identified emotional expressions in separate single and asynchronous dual-task designs. To extend earlier behavioral studies of cognitive effects in CMI, we recorded event-related potentials (ERPs) in the dual-task design. Though response times were slower for CMI patients across the two tasks, behavioral and ERP analyses indicated that patients did not differ from matched controls in the ability to allocate attentional resources between the two tasks. P1 ERP component analyses provided no indication of an emotional arousal deficit in our CMI sample while P3 ERP component analyses suggested a CMI-related deficit in emotional regulation. P3 analysis also yielded evidence for a frontalization of neurophysiological activity in CMI patients. Pain and related depression and anxiety factors accounted for CMI deficits in single-task, but not dual-task, response times. Results are consistent with a dysfunctional fronto-parietal attentional network resulting from either the indirect effects of chronic pain or the direct effects of CMI pathophysiology stemming from cervico-medullary compression.

Do silhouettes and photographs produce fundamentally different object-based correspondence effects?

When participants classify pictures of objects as upright or inverted with a left or right keypress, responses are faster if the response location (left/right) corresponds with the location of a handle (left/right) than if it does not. This result has typically been attributed to a grasping affordance (automatic activation of muscles associated with grasping the object with the ipsilateral hand), but several findings have indicated instead that the effect is a spatial correspondence effect, much like the Simon effect for object location. Pappas (2014) reported evidence he interpreted as showing that spatial coding predominates with silhouettes of objects, whereas photographs of objects yield affordance-based effects. We conducted two experiments similar to those of Pappas, using frying pans as stimuli, with our two experiments differing in whether the entire object was centered on the display screen or the base was centered. When the objects were centered, a positive correspondence effect relative to the handle was evident for the silhouettes but a negative correspondence effect for the photographs. When the base was centered, the handle was clearly located to the left or right side of the display, and both silhouettes and photographs produced correspondence effects of similar size relative to the handle location. Despite the main results being counter to the grasping affordance hypothesis, response-time distribution analyses suggest that, instead of activating automatically at fast responses, an effector-specific component of the hypothesized type may come into play for responses that are selected after the handle location has been identified.

Age-related emotional bias in processing two emotionally valenced tasks.

Previous studies suggest that older adults process positive emotions more efficiently than negative emotions, whereas younger adults show the reverse effect. We examined whether this age-related difference in emotional bias still occurs when attention is engaged in two emotional tasks. We used a psychological refractory period paradigm and varied the emotional valence of Task 1 and Task 2. In both experiments, Task 1 was emotional face discrimination (happy vs. angry faces) and Task 2 was sound discrimination (laugh, punch, vs. cork pop in Experiment 1 and laugh vs. scream in Experiment 2). The backward emotional correspondence effect for positively and negatively valenced Task 2 on Task 1 was measured. In both experiments, younger adults showed a backward correspondence effect from a negatively valenced Task 2, suggesting parallel processing of negatively valenced stimuli. Older adults showed similar negativity bias in Experiment 2 with a more salient negative sound ("scream" relative to "punch"). These results are consistent with an arousal-bias competition model [Mather and Sutherland (Perspectives in Psychological Sciences 6:114-133, 2011)], suggesting that emotional arousal modulates top-down attentional control settings (emotional regulation) with age.